FIG. 8 shows a conventional single-phase brushless motor 10 which comprises a stator 11 and a rotor 19 installed in the stator. The stator comprises a stator core 12 and a winding 13 wound on the stator core. The stator core comprises an annular yoke 14 and a plurality of teeth 15 extending inwardly from the yoke. Slots 16 are formed between adjacent teeth for receiving coils of the winding 13. The yoke 14 and the teeth 15 of the stator core are integrally formed into a single integral structure. Each tooth 15 forms a stator pole which comprises a pole shoe 18 formed at the end of the tooth. The pole shoe extends along the circumferential direction of the motor. A slot opening 17 is formed between each pole shoe to allow access for winding a coil about each tooth. Therefore, a non-uniform air gap is formed between the stator 11 and the rotor 19. In the above conventional single-phase brushless motor, the presence of the slot openings 17 may cause the motor to generate an unduly large cogging torque, thereby causing vibrations and noises. Furthermore, as the stator core is of an integral structure, a reciprocating shuttle winding machine is required for the winding process, which causes a low winding efficiency.